Vehicle for the remote handling of loads

ABSTRACT

A vehicle for the remote handling of loads, comprising a carrying structure (11) with a driving and steering wheel (32), and a fork structure (2) supported by the carrying structure so that it can be raised and lowered and provided with a hook (5) for connection to a vertically-movable attachment part(S) of a lift truck (C). The support structure has a simplified articulated-parallelogram conformation (11) connected to a rear frame (10) of the fork structure (2) and vertical movement of the latter is controlled by a single hydraulic linear actuator (36) vertically interposed between the rear frame (10) and the parallelogram structure (11).

DESCRIPTION

The present invention refers in general to vehicles for the remotehandling of loads.

More particularly, the invention relates to a vehicle comprising acarrying structure provided with a roller-like driving and steeringwheel and a fork structure supported by the carrying structure so thatit can be raised and lowered, in which the fork structure is providedwith hook means for connection to a vertically movable attachment partof a lift truck, and in which electro-hydraulic control means, connectedby flexible hoses to the lift truck, are provided for operating thedriving and steering wheel and the fork structure.

A vehicle for the remote handling of loads of the type defined above isdescribed and illustrted in Italian Pat. No. 1 054 432 and in thecorresponding British Pat. No. 1 453 387. In particular, this vehicleallows the operations of loading and unloading of packages relative tothe load platform of a lorry to be made easier and more convenient,since such operations can be carried out by the operator of the lifttruck from outside the lorry itself.

The vehicle according to these prior documents has the disadvantage ofhaving a complex, expensive, and heavy structure. In fact, in thisvehicle, the support structure consists of a heavy framework providedwith lateral rollers movable within suitable lateral guides formed onthe sides of the rear part of the fork structure. As well asconstructional difficulties, this conformation requires long andcomplicated manual assembly operations. The electro-hydraulic controldevices and the steering system for the driving wheel of this knownvehicle are also constructionally complicated.

The object of the present invention is to improve the known vehiclespecified above, by simplifying its structural parts and their assemblydrastically, while appreciably reducing the weight of the vehicle to thebenefit of its usable carrying capacity.

According to the invention, this object is achieved by virtue of thefact that the support structure of the vehicle comprises an articulatedparallelogram structure including a bar whose ends are articulated to arear frame of the fork structure, two vertical legs arranged on oppositesides of the driving wheel and carrying balancing support wheels attheir lower ends, a pair of upper arms carried by the horizontal bar andarticulated to the tops of the two vertical legs, and a pair of lowerarms articulated at one end to the vertical legs and at the other to therear frame of the fork structure, and in that the tops of the verticallegs are interconnected by a cross member parallel to the horizontal barand carrying the driving wheel underneath it, a single vertical linearhydraulic actuator for raising and lowering the fork structure relativeto the carrying structure being interposed between the middle region ofthe cross member and the rear frame of the fork structure.

This conformation is notably simpler than that known from theafore-mentioned prior documents, in that it eliminates the use ofrollers and associated rolling guides and drastically reduces the numberof components of the vehicle.

This simplification allows, among other things, the use of mechanisedassembly technology and appreciably reduces the total weight of thevehicle.

According to another characteristic of the invention there is fixed tothe cross member of the parallelogram structure a horizontal linearhydraulic actuator with a movable cylinder to the lower end of which isfixed a plate bearing a vertical pulling pin offset with respect to theactuator for rotation of a forked support articulated to the crossmember and carrying the driving wheel.

The driving wheel is driven by a rotary hydraulic actuator incorporatedtherein.

The invention will now be described in detail with reference to theappended drawings, provided purely by way of non-limiting example, inwhich:

FIG. 1 is a schematic perspective view of a handling vehicle accordingto the invention illustrated in an operative condition,

FIG. 2 is a front perspective view of the vehicle, FIG. 3 is a rearperspective view which shows the inside of the vehicle on an enlargedscale,

FIG. 4 is a view similar to FIG. 3 of a component of the vehicle on areduced scale,

FIG. 5 is an exploded front perspective view which shows anothercomponent of the vehicle,

FIG. 6 is a vertical section taken on the line VI--VI of FIG. 3, on anenlarged scale, and

FIG. 7 is a partially sectioned view taken on the line VII--VII of FIG.2.

With initial reference to FIG. 1, a vehicle according to the invention,generally indicated 1, can be used in conjunction with a conventionallift truck C for the remote handling of loads L. The vehicle 1 can beused to particular advantage for the loading and unloading of loads L.The vehicle 1 can be used to particular advantage for the loading andunloading of loads L relative to a loading platform P of a lorry A by anoperator M situated at the controls of the lift truck C, outside thelorry A.

With reference to FIG. 2, the vehicle 1 comprises essentially agenerally parallelepipedal rear body 2, from whose front side projecttwo horizontal forks 3 provided at their front ends with lower supportwheels or rollers 4, which can be lowered and raised in the manner madeclear below.

Two downward-facing hooking prongs 5 project rearwardly from the top ofthe body 2 and serve in known manner for engagement of the vehicle by avertically-movable support platform S of the lift truck C.

With reference in greater detail to FIGS. 2 and 3, the body 2 consists,in practice, of a sheet metal box with a vertical front wall 6, twovertical side walls 7 and a horizontal upper wall 8, as well as avertical rear wall 9 (FIG. 1) which is removable to allow access to theinside of the box.

This box does not have a structural function in practice, since it actssolely as a covering and protective part for the internal mechanism ofthe vehicle, and is fixed to a strong frame 10 to whose base the twoforks 3 are fixed.

A support structure, generally indicated 11 in FIGS. 3 and 5, relativeto which the body 2 carrying the forks 3 can be raised and loweredvertically in the manner made clear below, is connected to the frame 10.

The support structure 11 has generally an articulated parallelogramshape formed by a horizontal bar 12 whose ends 12a a are articulated at13 to the sides of the frame 10 of the body 2 and from which two upperarms 14 project. The free ends of the upper arms 14 are articulated at15 to two respective vertical legs 16 provided with balancing supportwheels 17 at their lower ends. Two fork-shaped lower arms 19, arearticulated at 18 to the lower regions of the two vertical legs 16 andare themselves articulated to respective attachment parts 20 carried onthe lower side of the frame 10 of the body 2.

The support structure 11 also includes a cross member 21 parallel to thehorizontal bar 12 and fixed rigidly at its ends to the tops of thevertical legs 16. This cross member 21 has a rectangular section and toits side opposite the vertical wall 6 of the body 2 are fixed twosupport brackets 22 between which extends horizontally a rod 23 of adouble-acting linear hydraulic actuator 24 whose cylinder 25 is axiallyslidable along the rod 23. The ends of the cylinder 25 are connected toa pair of vertical plates 26 interconnected by a horizontal plate 27carrying a vertical pin 28 to which a generally triangular lower plate29 is articulated. This plate 29, which is spaced from the plate 27,carries at its ends two vertical brackets 30 which rotatably support thepin 31 of a roller-like driving and steering wheel 32 incorporating areversible rotary hydraulic motor 33 of conventional type.

As clearly shown in FIG. 6, the pin 38 is offset with respect to thehydraulic actuator 24 and the plate 29 is articulated to the crossmember 21 by means of a vertical pin 34 positioned on the opposite sideof the actuator 24 to the pin 28. A thrust bearing 35 coaxial with thepin 34 is interposed between the plate 29 and the lower side of thecross member 21.

A substantially vertical linear actuator, generally indicated 36, isarticulated at its lower end, at 37, to an attachment part 38 projectingfrom the middle region of the side of the cross member 21 facing thevertical wall 6 of the body 2, and at its upper end, at 39, to anattachment 40 fixed in a corresponding position on the upper side of theframe 10.

The horizontal linear actuator 24, the hydraulic motor 33 and thevertical linear actuator 36 are connected by means of respectiveflexible inlet and outlet hoses to a solenoid control valve unit,generally indicated 41, carried on a support 42 fixed to the upper sideof the cross member 21 and connected in turn to a supply hose 43 and adischarge hose 44 for hydraulic fluid, as well as to an electricalsupply cable 45. The supply hose 43 leads, through a filter 46 to arespective connection union 47. The discharge hose 44 leads to arespective connection union 48 and the electrical supply cable 45 isconnected to a connection socket 49. The unions 47 and 48 and the socket49 are positioned in a recess 50 in the upper wall 8 of the body 2, andare connected respectively to a flexible supply line 51, a flexibledischarge line 52 and a plug 53 connected to an electrical supply cable54, which unwind from a winding reel V on the lift truck C. The lines 51and 52 and the cable 54 are connected respectively to a conventionalhydraulic unit and a conventional electrical control unit installed onthe lift truck C.

As better shown in FIG. 7, the support wheels 4 of the two forks 3 arecarried by respective bogies 55, each of which is articulated to apivoting arm 56 connected at one end to a respective chain 57. Thechains 57 pass around respective fixed guides 58 on the frame 10 and areanchored at their opposite ends to attachments 59 carried on thehorizontal bar 12. It is clear that, when the fork structure 2 and hencethe bar 12 are raised relative to the support structure 11, a downwardangular displacement of the arms 56 and hence of the bogies 55 carryingthe support wheels 4 occurs. Conversely, when the fork structure 2 andhence the bar 12 are lowered, the arms 56 and hence the bogies 55 areallowed to return to the raised position of FIG. 7.

Instead of the chain drive 57 described above, control of the raisingand lowering of the wheels 4 could also be achieved by means of a rigidtie rod, according to the method described and illustrated in the priorpatent documents mentioned above.

The operation of the handling vehicle 1 according to the invention is asfollows.

During movement to and from the working zone, such as, for example, theloading platform P of the lorry A illustrated, the vehicle 1 is normallycarried on the support plate S of the lift truck C by means of theengagement between the hooks 5 and the plate S.

In order to operate remotely in the working zone, the vehicle 1 is firstuncoupled from the support plate S and placed on the surface of theworking zone, for example on the platform P. At this point, the vehicle1 can be maneuvered remotely by the operator M at the controls of thelift truck C through the hydraulic lines 51 and 52 and the electricalsupply cable 54. Movement of the vehicle 1 is achieved by the action ofthe hydraulic motor 33 associated with the driving wheel 32, whilstmaneuvering is achieved through the steering of the wheel 32 by means ofthe horizontal linear actuator 24. In effect, displacements of thecylinder 25 in one direction or the opposite direction relative to theshaft 23 cause, through the offset pin 28, corresponding rotations ofthe plate 29 and hence of the wheel 32 about the axis of the pin 34 andthe thrust bearing 35.

The raising and lowering of the forks 3 (which, as stated previously,correspond respectively to the lowering and raising of the supportwheels 4) to pick up and put down the loads L is controlled by means ofthe vertical linear hydraulic actuator 36 whose actuation causes acorresponding displacement of the whole body 2 relative to the crossmember 21 and to the vertical legs 16 through the horizontal bar 12 andthe upper and lower arms 14, 19 of the support structure 11.

It is clear from the above that, by virtue of the conformation of thesupport structure 11 and the units for controlling the steering of thedriving wheel 32 and the raising of the fork structure 2, the vehicleaccording to the invention is provided with a simplified and lightenedstructure which can be manufactured and assembled in a particularlysimple and economical manner.

Naturally, the details of construction and forms of embodiment of thevehicle can be varied widely with respect to those described andillustrated, without thereby departing from the scope of the presentinvention as defined by the following claims.

I claim:
 1. A vehicle for the remote handling of loads, comprising acarrying structure provided with a roller-like driving and steeringwheel and a fork structure supported by the carrying structure so thatit can be raised and lowered, the fork structure having a rear frame andbeing provided with hook means for connection to a vertically movableattachment part of a lift truck, and electro-hydraulic control meansconnected to the lift truck being provided for the operation of thedriving and steering wheel and the fork structure, a support structurecomprising an articulated parallelogram structure including a horizontalbar having its ends articulated to the rear frame of the fork structure,two vertical legs situated on opposite sides of the driving wheel andcarrying balancing support wheels at their lower ends, a pair of upperarms carried by the horizontal bar and articulated to the tops of thetwo vertical legs, and a pair of lower arms articulated at one end tothe vertical legs and at their other ends to the rear frame of the forkstructure, a cross member parallel to the horizontal bar interconnectingthe tops of the vertical legs and carrying the driving wheel underneathit, and a single vertical linear hydraulic actuator for raising andlowering the fork structure relative to the carrying structure beinginterposed between the middle of the cross member and the rear frame ofthe fork structure.
 2. A vehicle according to claim 1, comprising ahorizontal linear hydraulic steering actuator fixed to the cross memberand having a movable cylinder, a plate fixed to the said movablecylinder and bearing a vertical pulling pin offset with respect to theactuator, and a forked support articulated to the cross member andcarrying the driving wheel, said forked support being rotated by thesaid pulling pin.
 3. A vehicle according to claim 1, wherein the drivingwheel incorporates a rotary hydraulic actuator.
 4. A vehicle accordingto claim 1, wherein said fork structure comprises forks which areprovided with respective lower support wheels which can be lowered andraised by the respective raising and lowering of the fork structure, anda chain drive anchored at one end to the horizontal bar of the supportstructure and at the opposite end to respective pivoted supportscarrying the support wheels for raising and lowering the said supportwheels.
 5. A vehicle for the remote handling of loads, comprising acarrying structure provided with a roller-like driving and steeringwheel and a fork structure supported by the carrying structure so thatit can be raised and lowered, the fork structure having a rear frame andbeing provided with hook means for connection to a vertically movableattachment part of a lift truck, and electro-hydraulic control meansconnected to the lift truck being provided for the operation of thedriving and steering wheel and the fork structure, a support structurehaving a generally articulated parallelogram shape and including ahorizontal bar having its ends articulated to the rear frame of the forkstructure, two vertical legs situated on opposite sides of the drivingwheel and carrying balancing support wheels at their lower ends, a pairof upper arms carried by the horizontal bar and articulated to the topsof the two vertical legs, and a pair of fork-shaped lower armsarticulated at one end to a lower portion of the vertical legs and attheir other ends to the rear frame of the fork structure, a cross memberpositioned and rigidly fixed parallel to the horizontal bar forinterconnecting the tops of the vertical legs mounted above the drivingand steering wheel, the cross member having a generally rectangularsection with two fixed support brackets between which a rod extendshorizontally, a horizontal linear hydraulic steering actuator having acylinder mounted upon said rod which cylinder can movably slide axiallytherealong, vertical plates fixed to each end of said movable steeringcylinder and bearing a vertical pulling pin offset with respect to theactuator, and a forked support articulated to the cross member andcarrying the driving and steering wheel, said forked support beingrotated by the said pulling pin; and a single vertical linear hydraulicactuator for raising and lowering the fork structure relative to thecarrying structure being interposed between the middle of the crossmember and the rear frame of the fork structure.
 6. A vehicle accordingto claim 5 wherein the vertical plates of the steering cylinder areinterconnected by a horizontal plate carrying said vertical pulling pin,and further wherein a lower articulated plate member is provided beneathsaid pin with a thrust bearing which is coaxial with said pin interposedbetween said pin and said lower plate member.
 7. A vehicle according toclaim 5, wherein the driving wheel incorporates a rotary hydraulicactuator.
 8. A vehicle according to claim 5, wherein the forks areprovided with respective lower support wheels which can be lowered andraised by the respective raising and lowering of the fork structure, anda chain drive anchored at one end to the horizontal bar of the supportstructure and at the opposite end to respective pivoted supportscarrying the support wheels for raising and lowering the said supportwheels.
 9. A vehicle for the remote handling of loads, comprising acarrying structure provided with a roller-like driving and steeringwheel and a fork structure supported by the carrying structure so thatit can be raised and lowered, the fork structure including a pair offorks provided with respective lower support wheels which can be loweredand raised by the respective raising and lowering of the fork structure,said fork structure having a rear frame and being provided with hookmeans for connection to a vertically movable attachment part of a lifttruck, and electro-hydraulic control means connected to the lift truckbeing provided for the operation of the driving and steering wheel andthe fork structure, a support structure consisting essentially of agenerally articulated parallelogram shape and including a horizontal barhaving its ends articulated to the rear frame of the fork structure, twovertical legs situated on opposite sides of the driving wheel andcarrying balancing support wheels at their lower ends, a pair of upperarms carried by the horizontal bar and articulated to the tops of thetwo vertical legs, and a pair of fork-shaped lower arms articulated atone end to a lower portion of the vertical legs and at their other endsto the rear frame of the fork structure, a cross member positioned andrigidly fixed parallel to the horizontal bar for interconnecting thetops of the vertical legs mounted above the driving and steering wheel,wherein the driving and steering wheel incorporates a rotary hydraulicactuator, the cross member having a generally rectangular section withtwo fixed support brackets between which a rod extends horizontally, ahorizontal linear hydraulic steering actuator having a cylinder mountedupon said rod which cylinder can movably slide axially therealong,vertical plates fixed to each end of said movable steering cylinder andbearing a vertical pulling pin offset with respect to the actuator, anda forked support articulated to the cross member and carrying thedriving and steering wheel, said forked support being rotated by thesaid pulling pin, wherein the vertical plates of the steering cylinderare interconnected by a horizontal plate carrying said vertical pullingpin, and further wherein a lower articulated plate member is providedbeneath said pin with a thrust bearing which is coaxial with said pininterposed between said pin and said lower plate member; and a singlevertical linear hydraulic actuator for raising and lowering the forkstructure relative to the carrying structure being interposed betweenthe middle of the cross member and the rear frame of the fork structure.